Largest earthquake centered in Taipei in the past 26 years
By Joy Lee, The China Post
February 13, 2014, 12:02 am TWN
TAIPEI, Taiwan -- The 4.0-magnitude earthquake with its epicenter located in Taipei City's Shilin District was the most intense earthquake originating in Taipei City in the past 26 years, the Central Weather Bureau (CWB) said yesterday.
According to the CWB, the earthquake, which took place at 12:31 in the morning of Feb. 12, was the largest earthquake with its epicenter located in Taipei City since the 5.3-magnitude earthquake that occurred in 1988.
Even though many people are concerned that this earthquake might be a sign of the eruption of the Tatun Volcano Groups, Director of the CWB Seismology Center Kuo Kai-wen (郭鎧紋) said that based on the historical records, the frequency of earthquakes that are triggered by Tatun Volcano Groups is still within the regular range.
“This earthquake that took place on Wednesday morning was a result of the cooling process of a magma reservoir,” said Kuo. “Some cracks were generated due to the contraction from the cooling process, and the laccolith that caused the earthquake collapsed.”
“If there are 200 to 300 magnitude-1 earthquakes within one day, that is irregular,” said Kuo. “Therefore, the earthquake is not a sign of the eruption of the Tatun Volcano Groups.”
In response to some experts' opinions saying that it is irregular to have an earthquake with a greater than magnitude-4 epicenter located in Taipei City, Kuo said that the Tatun Volcano Groups on average cause an earthquake that reaches more than magnitude-4 every 10 to 20 years and the volcano groups also cause a magnitude-3 earthquake every one to two years.
“So far the earthquake frequency of the Tatun Volcano Groups is within the regular range,” said Kuo.
According to the CWB, there is no sign of intense activity caused by the Tatun Volcano Groups.
The CWB said that the depth of the earthquake was 6.3 kilometers and the largest intensity in Yangmingshan National Park was magnitude 4 and the quake in New Taipei City and Taoyuan City was magnitude 3.
The Taipei Feisui Reservoir Administration yesterday said that after the earthquake took place, the officials conducted a series of safety inspections and confirmed that the reservoir was still safe and stable.
The administration said that the intensity at the reservoir area was lower than magnitude 1 and the reservoir is located on top of a hard laccolith, so there was no damage.